The episodes are being presented in order of numbering. The airdates are in a slightly different order.

Episode Title: 'Wolf in the Fold'
Synopsis: "During shore leave on a luxurious planet, a serial murderer strikes, and all evidence points to Scotty as the criminal until an investigation reveals that the killer may be an ancient being who has plagued Earth."

Episode Title: 'The Changeling'
Synopsis: "A powerful probe called Nomad, the hybrid of an Earth probe and an alien machine, mistakes Kirk for its creator and tells him of its plan to destroy all impurity - including the imperfect organic crew of the Enterprise."

Episode Title: 'The Apple'
Synopsis: "An ancient machine in the form of a dragon controls the primitive inhabitants of a world which lives to serve; Kirk and his crew try to make the natives see how much they could accomplish if they were free."

Episode Title: 'Mirror, Mirror'
Synopsis: "Four crewmembers switch places with their parallels in another universe, where savagery reigns and advancement is by assassination. While Spock quickly realizes the situation and takes the alternate Kirk, McCoy, Scotty and Uhura into custody, Kirk must first try to evade detection and then convince the alternate Spock of the logic of changing his universe."

Episode Title: 'The Deadly Years'
Synopsis: "Kirk and many crewmembers are exposed to a disease which causes them to age rapidly, while the ship comes under attack after a dangerous decision by an afflicted Starfleet officer."

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Keeper of the Jabberwock

Mirror, Mirror is probably the most interesting of the bunch here.
The Changeling was also good--probably better than the movie that brought the franchise back to life.

The Apple was a little too obvious for my taste.
The Deadly Years had a bit of bad biology, which probably colors my dislke for it.
Wolf was a nice mystery, but how come every ephemeral being winds up in the ship's computers?

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Keeper of the Jabberwock

"Mirror, Mirror" is exceptional by how many follow-on stories that were based on it: A few in DS9, and a couple (that I finally watched on Scifi channel) on Enterprise. I liked "Mirror, Mirror," though it isn't in my top five.

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I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

I liked Mirror Mirror - there was even a variant of it in a book called something like "The unfinished Star Trek" It was meant to be stories accepted by Roddenberry but never made into actual shows. In the unshot one, the actors accidently take the place of their characters on the ship

I adored the Changeling - even the movie version

I really like the closing line from the evil Spock in Mirror, Mirror, when good Kirk explains how the tantalus field could allow Spock to affect change for the better.

"Captain Kirk, I will consider it."

These polls are fun. A real trip down memory lane.

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Observatorio de la Ballona

Hey, I was really hoping to see some good discussions of episodes on these polls, considering that probably the majority of posters have seen some or most of the epsiodes.

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Keeper of the Jabberwock